by Sean Highkin, USA TODAY Sports

by Sean Highkin, USA TODAY Sports

Chicago Bulls guard Derrick Rose injured his right knee during the third quarter of the team's 98-95 loss to the Portland Trail Blazers on Friday night and did not return.

The severity of the injury is not yet known - the Bulls classified it simply as a "right knee injury" - but there was no contact on the injury. Following the injury, the 2010-11 NBA MVP could not put weight on the knee and had to be helped to the locker room by two trainers.

According to a person with knowledge of the situation, Rose will have an MRI mid-afternoon Pacific Time. The person spoke to USA TODAY Sports on the condition on anonymity because the time hasn't been announced.

Rose had 20 points and five rebounds before his departure.

Bulls coach Tom Thibodeau said during the his post-game news conference that Rose would have an MRI on Saturday in Los Angeles.

"I'm concerned" Thibodeau said. "Anytime anyone goes down, you're concerned. But I don't want to speculate until we have more information."

Thibodeau added that Rose, who left the Moda Center on crutches, could not push off on the knee.

Rose sat out the entire 2012-13 season after tearing the anterior cruciate ligament in his left knee during the 2012 playoffs. His Friday injury was not to the same knee, although he dealt with issues with his right hamstring earlier this season.

Rose's injury comes two games into a six-game road trip in which the Bulls have lost the first two games. Chicago is already without starting shooting guard Jimmy Butler, who is week-to-week with turf toe.

"Hopefully, it's nothing serious," teammate Taj Gibson said. "He's a strong guy. He worked extremely hard this summer trying to get his body right, working out every day."